The lettuce that we cultivate on a mass scale today is descended from a once wild vegetable originally found in the
Near East
and the
Mediterranean
.
Its name is derived from the Latin word "lac" which means "milk", which
the French then changed to "laitue" ("lait" being the French word for
milk), and the English later altered to "lettuce". The name refers to
the milky juice exuded by the vegetable.
Lettuce
has been around for a long time. It is reported that Persian kings
would eat lettuce around 550 BC and Hippocrates spoke of its
nutritional values only a century later. The Greeks and Romans consumed
much lettuce and knew of all the different varieties, but we do not
hear of it in Britain until much later, around the late 14th century in
Chaucer’s prologue to the Canterbury Tales.
There
are a number of different lettuces today and many have been hybridised
to withstand the rigours of large-scale harvesting and long-distance
transportation, but there are two main distinctive categories available:
1.
Cabbage
lettuce: these have football-shaped heads of soft leaves that damage
easily. Varieties include Dutch lettuce (the softest sorts) and Webb's
Wonder.
2.
Cos lettuce: known by the Americans as
Romaine lettuce, after the Romany region in
Italy
where
they are believed to have originated. They have longer leaves and
elongated heads and are coarser and crisper than cabbage lettuces.
Medicinal Value
Lettuce
tops the lists of foods eaten most by people with the lowest incidence
of serious disease, along with other green and orange vegetables.
Lettuces, especially the dark green varieties, contain large amounts of
vitamin A and C. These two vitamins are vital in the body’s fight
against cancer as they work on many levels to prevent and cure, or
fight against all sorts of serious disease.
Firstly,
vitamin C, abundant in lettuce and other dark green vegetables, helps
to strengthen the immune system against infection. A healthy immune
system will be far more resilient to infections like colds and coughs.
Vitamin C is also an antioxidant. An antioxidant is something that will
neutralise oxygen free radicals in the body’s cells by reacting
chemically with them. The more antioxidants in the cells the more
likely these chemical reactions are to occur, decreasing the likelihood
of oxygen free radicals causing mutations of cells. Oxygen free
radicals are mutagenic, and get into the body in numerous ways,
including smoking, pesticides on food and air-borne pollutants. This
nutritional defence is essential for people exposed to such chemicals
in order to avoid illness.
The
pro-vitamin A in lettuce, which is a yellow/red colour, would normally
change the colour of the vegetable to dark orange, however, the
green-coloured chlorophyll in the leaves masks this, making the plant
green. There are still massive quantities of pro-vitamin A in lettuce,
however, in the form of beta carotene, another antioxidant.
Lettuce
is also high in fibre, the stringy, indigestible veins in the leaves
and stems. These are taken into the stomach, but are not broken down,
so the body excretes them through the rectum. Eating constant amounts
of fibre encourages regular excretion of harmful chemicals from the
stomach, reducing the likelihood of serious disease of the stomach,
colon and rectum. Cos lettuce contains much more fibre than cabbage
lettuce, although both are high in fibre.
Cooking Lettuce
Cooking
lettuce in water will tend to decrease its nutritional value, as
chemical reactions in the water and vegetable break down such compounds
as vitamin C. The best way to cook it is to steam it quickly over a
small amount of water. This happens too quickly for any real reactions
to occur. When serving raw in salad it is counter-productive to nullify
the nutritional value by dowsing in high-fat dressing. Instead try just
a little oil and lemon juice dressing.
